(a) Field of the Invention
The present invention relates to liquid crystal displays (LCDs) and manufacturing methods thereof.
(b) Description of the Related Art
In LCDs, an electric field is applied to liquid crystal material injected between two substrates, an array substrate and a counter substrate, arranged substantially parallel to one another with a predetermined gap therebetween. Formed on the array substrate are a plurality of gate lines disposed parallel to one another, and a plurality of data lines insulated from and crossing the gate lines. A plurality of pixel electrodes are formed corresponding to respective regions defined by the intersecting data lines and gate lines. Furthermore, a thin film transistor (TFT) is provided near each of the intersections of the gate lines and the data lines. Each pixel electrode is connected to a data line via a corresponding TFT, the TFT serving as a switching device therebetween.
Such TFT-LCDs are formed by laying a plurality of thin films, one at a time, and etching the same. However the films tend to break open in certain areas, causing a disconnection of the portion of the films. To prevent this, the data lines are doubled at portions where they overlap the gate lines. A metal layer may also be deposited and patterned either over or under the data lines, following the pattern of the same to form repair lines.
In the first method, the data lines disconnected in areas other than the intersection require additional lines to repair the damaged portion. Furthermore, a laser junction process used to repair the disconnected data lines may not be easily applied to high-resolution displays.
Since the second method deposits and patterns the metal layer to form the repair lines and subsequently deposits and etches an insulating layer to connect the repair lines to the data lines, the overall LCD manufacturing process becomes complicated due to the additional steps.
An LCD having a couple of gate lines in a pixel may be used to prevent defects by the disconnection of the gate line. The LCD includes a couple of the gate lines parallel to each other, and a connecting line that links the gate lines. A secondary line to repair the disconnected data lines is formed in parallel with the connecting line, and a data line overlaps the secondary line. Since the secondary line and the data line are electrically connected to each other, data signals are transmitted through the secondary line when the data line is disconnected.
However, the narrow space between the secondary line and the connecting line increases a coupling capacitance between the data line and the connecting line and delays the digital signal. Furthermore, the connecting line and the secondary line may be short-circuited by conductive particles.